Slurry feeding arrangement

Abstract

A slurry feeding arrangement, flotation cell, line, and a method for treating particles suspended in slurry. The slurry feeding arrangement comprises one or more slurry feed means configured to feed slurry to a froth layer; a feed chamber configured to receive the fed slurry from the one or more slurry feed means; an overflow ramp between the feed chamber and the froth layer configured to lead the slurry from the feed chamber to the froth layer.

1 . A slurry feeding arrangement configured to feed slurry to a froth layer, the slurry feeding arrangement comprising
 one or more slurry feed means configured to feed the slurry;   a feed chamber configured to receive the fed slurry from the one or more slurry feed means; and   an overflow ramp between the feed chamber and the froth layer configured to lead the fed slurry from the feed chamber to the froth layer.   
     
     
         2 . The slurry feeding arrangement according to  claim 1 , comprising a feed means connector connectable to the one or more slurry feed means, wherein the feed chamber is placed under the feed connector and arranged to receive the fed slurry from the one or more slurry feed means. 
     
     
         3 . The slurry feeding arrangement according to  claim 2 , wherein the feed means connector comprises a top plate having one or more feed openings, through which the fed slurry is arranged to enter the feed chamber and/or compartments. 
     
     
         4 . The slurry feeding arrangement according to  claim 1 , wherein the feed chamber comprises a feed chamber bottom and a slurry overflow lip located above the feed chamber bottom; and an overflow ramp extending obliquely downwards from the slurry overflow lip, wherein the fed slurry is configured to flow from the feed chamber over the slurry overflow lip onto the overflow ramp during operation of the slurry feeding arrangement. 
     
     
         5 . The slurry feeding arrangement according to  claim 4 , wherein the feed chamber is ring-shaped, and the slurry overflow lip is arranged on the perimeter of the feed chamber. 
     
     
         6 . The slurry feeding arrangement according to  claim 1 , wherein the feed chamber is divided into one or more separate compartments by one or more partition walls. 
     
     
         7 . The slurry feeding arrangement according to  claim 1 , wherein the overflow ramp is arranged at an angle of 10 to 60 degrees to the horizontal. 
     
     
         8 . The slurry feeding arrangement according to  claim 1 , wherein the slurry overflow lip is ring-shaped, and the overflow ramp encircles the slurry overflow lip. 
     
     
         9 . The slurry feeding arrangement according to  claim 1 , wherein the slurry feeding arrangement comprises feeding strips extending from the lower edge of the overflow ramp and arranged at a distance from each other in the direction of the lower edge. 
     
     
         10 . The slurry feeding arrangement according to  claim 9 , wherein the ends of the feeding strips are connected to a lower edge of the overflow ramp, and the feeding strips taper towards their second ends. 
     
     
         11 . The slurry feeding arrangement according to  claim 9 , wherein the feeding strips are triangular in shape. 
     
     
         12 . The slurry feeding arrangement according to  claim 1 , wherein the slurry feeding arrangement comprise one or more downward sloping guiding plates placed under the lower edge of the overflow ramp and/or the feeding strips. 
     
     
         13 . The slurry feeding arrangement according to  claim 1 , wherein the one or more slurry feed means are configured to feed the slurry by gravity. 
     
     
         14 . The slurry feeding arrangement according to  claim 1 , wherein the feed chamber is configured to operate in atmospheric pressure. 
     
     
         15 . The slurry feeding arrangement according to  claim 1 , wherein the slurry feeding arrangement further comprises at least one gas bubble arrangement configured to feed gas bubbles into the feed chamber and/or on the overflow ramp. 
     
     
         16 . The slurry feeding arrangement according to  claim 15 , wherein the at least one gas bubble arrangement comprises one or more gas feed means configured to feed the gas bubbles into the feed chamber and/or on the overflow ramp. 
     
     
         17 . The slurry feeding arrangement according to  claim 16 , wherein the one or more gas feed means are configured to feed gas bubbles inside the feed chamber (through the top plate, feed chamber bottom, and/or one or more feed chamber sidewalls. 
     
     
         18 . The slurry feeding arrangement according to  claim 15 , wherein the at least one gas bubble arrangement is configured to feed the gas bubbles on the overflow ramp, wherein the one or more gas feed means are arranged to provide the gas bubbles over the width of the overflow ramp perpendicular to flow of the slurry. 
     
     
         19 . The slurry feeding arrangement according to  claim 15 , wherein the overflow ramp comprises a ramp bottom, wherein the gas bubble arrangement is configured to feed gas bubbles on the overflow ramp at a distance from the lower edge of the overflow ramp. 
     
     
         20 . The slurry feeding arrangement according to  claim 19 , wherein the ramp bottom has at least one of the following form: a curved, stepped, and/or corrugated. 
     
     
         21 . The slurry feeding arrangement according to  claim 16 , wherein each of the one or more gas feed means comprises one or more nozzles or outlets. 
     
     
         22 . The slurry feeding arrangement according to  claim 1 , wherein the overflow ramp comprises a ramp surface, a ramp bottom and a weir, wherein the ramp surface is
 arranged towards the froth layer;   configured to slope towards the froth layer and downwards towards the ramp bottom; and   configured to rise up from the ramp bottom towards the weir.   
     
     
         23 . The slurry feeding arrangement according to  claim 1 , wherein the slurry feeding arrangement comprises 1 to 512 slurry feed means. 
     
     
         24 . A flotation cell for treating particles suspended in slurry, wherein the flotation cell comprising
 a tank for holding a volume of slurry and a froth layer over the volume of slurry; and   a slurry feeding arrangement according to  claim 1 .   
     
     
         25 . The flotation cell according to  claim 24 , wherein the feed chamber has an annular or circular shape, and it is arranged concentric to a tank side wall. 
     
     
         26 . The flotation cell according to  claim 24 , wherein the one or more slurry feed means are arranged concentric to the tank side wall of the flotation cell. 
     
     
         27 . The flotation cell according to  claim 24 , wherein the one or more slurry feed means are arranged above the froth layer. 
     
     
         28 . The flotation cell according to  claim 24 , wherein the slurry feeding arrangement (is configured to feed the slurry onto the froth layer, into the froth layer, into the froth slurry interface, and/or immediately below the froth layer. 
     
     
         29 . The flotation cell according to  claim 24 , wherein the flotation cell further comprises a launder with a launder lip for collecting froth from the froth layer. 
     
     
         30 . The flotation cell according to  claim 24 , wherein the flotation cell further comprises one or more froth crowders arranged to direct froth towards a launder. 
     
     
         31 . A flotation cell according to  claim 24 , wherein the flotation cell comprises a flotation gas supply arrangement for supplying flotation gas into the volume of slurry below the slurry feeding arrangement. 
     
     
         32 . A method for treating particles suspended in slurry in a flotation cell according to  claim 24 , the method comprising
 providing a tank for holding a volume of the slurry and a froth layer over the volume of the slurry;   feeding, by a slurry feeding arrangement comprising one or more slurry feed means, the slurry to a feed chamber;   receiving, by the feed chamber, the fed slurry from the one or more slurry feed means; leading the fed slurry, by an overflow ramp between the feed chamber and the tank, from the feed chamber to the froth layer; and   feeding gas bubbles, by one or more gas bubble arrangements, to the fed slurry before the fed slurry enters to the froth layer.